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DOE OSTI · 3010699

Low two-level-system noise in hydrogenated amorphous silicon

Defrance, Fabien [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000237465296)·Beyer, Andrew D. [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000210451652)·Wheeler, Jordan [National Institute of Standards and Technology, Boulder, CO (United States)] (ORCID:0000000316785570)·Sayers, Jack [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000282133784)·Golwala, Sunil R. [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000210987174)
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Abstract

At sub-Kelvin temperatures, two-level systems (TLSs) present in amorphous dielectrics source a permittivity noise, degrading the performance of a wide range of devices using superconductive resonators such as qubits or kinetic inductance detectors. We report here on measurements of TLS noise in hydrogenated amorphous silicon (a-Si:H) films deposited by plasma-enhanced chemical vapor deposition in superconductive lumped element resonators using parallel-plate capacitors. In conclusion, the TLS noise results presented in this article for two recipes of a-Si:H improve on the best results achieved in the literature by a factor >5 for a-Si:H and other amorphous dielectrics and are comparable to those observed for resonators deposited on crystalline dielectrics.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYAmorphous materialsCapacitorsChemical vapor depositionDielectric materialsLow temperature detectorsResonator deviceSiliconSuperconducting devicesSuperconducting quantum computing

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Defrance, Fabien [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000237465296), Beyer, Andrew D. [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000210451652), Wheeler, Jordan [National Institute of Standards and Technology, Boulder, CO (United States)] (ORCID:0000000316785570), Sayers, Jack [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000282133784), Golwala, Sunil R. [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000210987174). 2025-03-25. Low two-level-system noise in hydrogenated amorphous silicon. https://doi.org/10.1063/5.0255172

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